Whew, I promised Paul I'd do four posts a day for five days and it has taken me a couple of hours just to read this post or link or what ever it is. The guy who started this discussion mentioned my good friend rob roy's attitude about using insulation on underground housing. That is, or was the attitude of the great number of underground architects for many years. I had a long running disagreement with them. Though it is true that the earth is a poor insulator that very fact is of benefit to the underground dweller. In the winter the earth around the house warms and when the fire is low at night or when you are away from home for an extended period -- weeks, say -- the earth will transfer heat into home keeping the pipes and food from freezing. It won't to that if the walls and floors are insulated. Nor will the earth keep the home nearly as cool in the summer if there is insulation. The other architects and I seem to have come to a sort of compromise: We insulate the roof, definitely the roof, and down to the frost line which in my country (North Idaho) is three feet; Rob's (n. New York) four feet. Rob and Jackie, incidentally, don't live in an underground house. Only their north wall is earthen bermed.

I have looked at the umbrella architecture type home for a few years and disagree with the method to a degree. The way they work is heating the air inside the home during the summer and the earth draws that heat out of the structure and stores it. They have tested similar designs and they found that the structure needed to maintain an uncomfortable temperature during the summer if it were to store enough energy to provide heat all winter. When controlling the temperature inside during the summer it would only supplement the heat required in the winter. It did work, but only to a degree. The earth covered structure is cooled during the summer and heated during the winter, but again, only to a degree. If the earthen mass is 55 degrees in the winter and you heat that structure to 70 degrees, the earthen mass is then drawing off the supplemental heat within the structure.

The system I came up with is building a separate structure for the collecting and storing of the heat in the thermal mass. The living structure would then be of a more conventional type and the heat would be brought in from the mass storage via air tubes and a fan. In the summer the air is drawn in from unheated earth and would cool the living structure. During the winter that same air would be diverted through the heated mass and heat the structure. By diverting the air during the winter that is used for cooling during the summer, you are prewarming it to the normal temperature of the soil (which is warmer then the outside air) before it is heated in the thermal mass. A heat pump. The heating structure could reach temperatures far above what is comfortable in the summer and heat the earthen mass enough that no other heat source would be required all winter. The fan would utilize a thermostatic control in the summer and winter.

I have seen references that would insulate a living structure from the earthen mass and can't figure out why anyone would go through all the engineering and efforts of a structure covered with earth and then insulating it from that earthen mass. That in my mind is defeating the benefits of an earth covered structure. Am I missing something

With my method I believe Leah and others are right in the thoughts of using a cargo container(s) for a living structure. My thoughts on that would be mixing cement and vermiculite as an insulator type stucco. It could be used on the interior and exterior of the cargo container. That would finish off the interior walls and protect the metal from oxidation if done right. I have not experimented with the vermiculite and cement mixture yet at all. In my experience with cement and metal, the cement has caused oxidation in the metal. A good undercoat and a rubberized paint may protect the container. Another thought would be using the new coatings applied to the beds of trucks. Anyone have any experience with cement mixed with vermiculite?

Posts: 9

posted 7 years ago

This is an engineering and cost problem. In the method I posted before you have an extra underground structure that needs to be engineered so it can support the weight of the heavy soil earthen mass (clay) and the insulating light soil surrounding it (sand). Difficult and expensive.

No need whatsoever. As many of you have probably searched the Internet and found the water storage and radiator systems I shouldn't have to go into it in much degree. The radiator is installed below the water storage tank and as the water is heated by the sun it rises out of the top of the radiator to the top of the storage tank. The cooler water in the tank sinks to the bottom of the tank and then the radiator as it's cooler then what is exiting the radiator. This occurs as long as the water is heated in the radiator hotter then the water is in the tank. There is what is called inversion and a one way valve needs to be installed so it doesn't work in reverse under some conditions. What's nice is that this system is self pumping and requires no external pump or power.

Simply apply the basics of both systems. Your tank now consists of self supporting tubing (PVC?) buried within the earthen mass. Instead of a water tank storing the heat, the earthen mass stores the heat. The hot water going into the mass will cool due to the mass drawing off the heat. That water then sinks and the self pumping action occurs as long as the input into the mass is above the the radiator.

Carrying this even farther, you could heat the living structure from this if it was above the heated earthen mass that stores all this heat. Keep in mind that this earthen mass is super heated all summer. All you need is a control valve allowing the heat to rise or be shut off or slowed and it would work the same way as the radiator and water storage tank only in reverse. Radiators would release the heat into the living structure and that would cool the water, it would then sink back into the earthen mass. Again this is self pumping and requires no external source of power.

That's a simplified version of my super heated heat pump. I'm simply making my own geothermal heat source added to the system. Heating the living structure may be a little more complicated, however it is being done with water stored in a tank and the same principles should apply.

This has never been tested by me or anyone else that I know of. It's just a few years of investigating heating sources and coming up with ideas. My mind works in funny ways sometimes and I would request any thoughts and/or suggestions about this system.

Posts: 9

posted 7 years ago

One thing I didn't mention in this hot water system is that a liquid will not compress. Hot water will expand causing pressure in the system and MUST be vented so the pressure is released or it could blow up. You are also working with VERY HOT water in the radiator.

CAUTION!!! Study some designs and insure you do any of this with safety in mind.

With that said, your on your own when using what I have written or experimenting with it. I wont be held responsible for the actions of others. We're all big people here (I hope) and you have the methods to research all this before attempting any of it.

Just thought I better add that as I can't afford a lawsuit and even more, I wouldn't want someone to get hurt. I plan on experimenting with this system in the future so if your not comfortable or knowledgeable enough, let someone else work out the problems before you try it and get hurt. What I have written here is just an idea and not a proven system for usage or safety.

Mike Oehler

author

Posts: 60

Location: Bonners Ferry Idaho

1

posted 7 years ago

1

This all sounds to me like a heck of a lot of work and expense for little gain, Ray. Here in N. Idaho the earth stays at 52 degrees year around eight feet below the surface. When it is zero degrees outside most houses most of my house has a 52 degree advantage. That's 52 degrees I don't have to heat. When it is 100 degrees outside most peoples houses it is 52 degrees outside of most of mine. That's a 48 degree advantage in cooling. My ideal is to keep life simple.

At 52 degrees in the winter I'll guess that you would heat an extra 18 degrees and have 70 degrees indoor. My system should raise that 18 degrees free after it's built. You pay for that 18 degrees. The mass surrounding your house would also work at drawing that 18 degree difference out of your house. Same in the summer with cooling the house, that 48 degrees costs and my system uses a fan pulling air through a tube buried in the ground. Can you cool that 48 degrees cheaper then that?

I would also say that burying part or all of a structure is also at a cost, not to mention the support required in building it so it supports the weight.

Not saying you don't have a good idea and thing going, but could it be improved? Is burying PVC more expensive or more work then burying an entire (or even part of a) house in your system? Just putting an idea out there that I think would be very cost effective and maybe a good system for adding on your type structure or any other.

Mike Oehler

author

Posts: 60

Location: Bonners Ferry Idaho

1

posted 7 years ago

A hilltop is actually a great place for an underground house: It drains beautifully. It also affords spectacular views. And in my case it is the only place I can get abundant sun. Fire is a big consideration, yes, but when I get my pond in I will have abundant water to wet down the surrounding forest.

Sounds like a wonderful place that many of us can only dream about at this point of our lives.

Good luck and ENJOY!!!

Posts: 31

posted 7 years ago

The first question I had for Mike was regarding termites.

I live in the extreme deep south, in a sub tropical climate also known as termite hell. My existing structure is an old added on to shack that sits on piers, one of the additions is on a slab with a 16 inch concrete wall. I have knocked down termite tunnels up the concrete, piers and wall, actually been so desperate I sprayed the concrete with industrial termite poison, and gone out the NEXT day and done it again!!!

Since I am totally opposed to the toxins and they make me sick it was a last resort as I am trying to keep a roof over myself until I can construct something else but the termites here are so fierce they will tunnel feet up the concrete to get to the pressure treated joists I had to install because the place was sinking. The termites had no problem going straight for the pressure treated wood either, I've also seen them eat styro foam and other things you'd never expect.

Orange oil is awesome, however, it is highly flammable, it also dissipates in 3 days. As I said the termites are a desperate situation for me so I bought a 55 gal drum of orange oil and soaked everything including a new wall inside before closing it up, it does kill the termites but they come back within a few months.

Mind you we have both the sub terranien and flying type, so they go for wood anywhere they can get it including the roof, they love the open overhang where the rafters meet the sheathing.

We had a lot of downed trees from Hurricane Dolly and the termites have been as happy to eat the mesquite as well as the ash, hack berry, and cedars, so I've no idea what species might really be even semi safe, maybe yew? They do seem to prefer softer wood which I am basing on the fact that the oldest wood in the house (20's) is the last they opt for, they will eat the 'new' 2x4 sandwiched to an old one first.

The sand idea has some promise but getting the 'right size' could be a problem, and having it stay that way, not being infiltrated by other soil or water.

I haven't found a solution other than steel and concrete which I 'll comment on separately. I've lived all over the US and had never seen termites like this. It becomes the first question I have to think on for any design or idea, earthen floors? cob, etc.

Posts: 31

posted 7 years ago

Since I first saw earth sheltered houses in Mother Earth News decades ago I have been enamored. Also had several basements and really appreciated many of the benefits. Bought a perfect solar sited hillside in Eugene to build into, that lot is currently available, and would make an awesome 2 story earth sheltered home.

So now I am transplanted to an area that I am not deadly allergic to and have largely flat land. Unlike most of the country I also rarely need to even think about heating. Cooling is another matter however, and so below ground is especially attractive. Ah but wait the earlier post regarding termites is still a huge factor.

The other big issue we have here is a soil and climate where moisture is a big problem, I can dig down 3' and have very moist soil, and that's not during rainy season. So I 'suppose berming is the only option, with lots of built in drains and such. And until I read this new discussion hadn't thought much about it since the most likely option for a 'low cost' structure is metal. So I'm wondering about options that use the principles but not wood. Any Ideas?

Serenity wrote: Since I first saw earth sheltered houses in Mother Earth News decades ago I have been enamored. Also had several basements and really appreciated many of the benefits. Bought a perfect solar sited hillside in Eugene to build into, that lot is currently available, and would make an awesome 2 story earth sheltered home.

So now I am transplanted to an area that I am not deadly allergic to and have largely flat land. Unlike most of the country I also rarely need to even think about heating. Cooling is another matter however, and so below ground is especially attractive. Ah but wait the earlier post regarding termites is still a huge factor.

The other big issue we have here is a soil and climate where moisture is a big problem, I can dig down 3' and have very moist soil, and that's not during rainy season. So I 'suppose berming is the only option, with lots of built in drains and such. And until I read this new discussion hadn't thought much about it since the most likely option for a 'low cost' structure is metal. So I'm wondering about options that use the principles but not wood. Any Ideas?

You might look at sixnone's earlier post... He used Earthship design for the bottom and then a rammed earth or cobb on up then a ferrocement roof.

Sometimes the answer is not to cross an old bridge, nor to burn it, but to build a better bridge.

Serenity wrote: So I 'suppose berming is the only option, with lots of built in drains and such. And until I read this new discussion hadn't thought much about it since the most likely option for a 'low cost' structure is metal. So I'm wondering about options that use the principles but not wood. Any Ideas?

How does an above ground Earthbag structure sound Serenity?

You will obviously have to check your local zoning laws, but you could potentially build the whole structure without wood. Domed structures are easy to build and are very strong, and the 3D shape of the roof combined with "Wind scoops" could be used for cooling. (These ideas are from "Ceramic houses and Earth architecture" by Khalili if you're interested.)

and since we have Mike Oehler's venerable presence for a few days, I'd love to check in with him on this as well.

So Mike, just wondering if you've come into contact with the earthbag building idea (as developed at Cal Earth and further popularised by Kaki Hunter and Donald Kiffmeyer in their book "Earthbag Building&quot, and if so I'd love to hear your personal opinion on its "underground" applications.

"The greatest learning takes place in dialogue between people - learning is a social process and not just an intellectual event"

Seems like somewhere in my reading, I've seen a picture of an earthbag house that was underground, or at least earth-bermed.

Kathleen

Mike Oehler

author

Posts: 60

Location: Bonners Ferry Idaho

1

posted 7 years ago

Sounds like you have the Asian (Korean, I think) termites who came ashore ten or so years ago, Serenity. They were said to chew through just about anything. They were devouring New Orleans before Katrina. I wouldn't try to fight them. Rob's earthbag suggestion sounds much more feasible and, yes, I think it should have an application underground. I was working by phone with Khalili's daughter on a project to use them underground on the Pine Ridge reservation in South Dakota till I learned that the soil there was oozy clay and the frost line four feet deep, the worst combination I could immagine. That clay freezes and expands greatly exerting horrendous pressure. I withdrew from the project and tried to warn them but never heard back. But, yeah, definately worth a shot. Start small, see how it goes, then add on.

Mike Oehler wrote: Sounds like you have the Asian (Korean, I think) termites who came ashore ten or so years ago, Serenity. They were said to chew through just about anything. They were devouring New Orleans before Katrina. I wouldn't try to fight them. Rob's earthbag suggestion sounds much more feasible and, yes, I think it should have an application underground. I was working by phone with Khalili's daughter on a project to use them underground on the Pine Ridge reservation in South Dakota till I learned that the soil there was oozy clay and the frost line four feet deep, the worst combination I could immagine. That clay freezes and expands greatly exerting horrendous pressure. I withdrew from the project and tried to warn them but never heard back. But, yeah, definately worth a shot. Start small, see how it goes, then add on.

Mike, we've got 'oozy' clay here, too (at least it's oozy when it's wet -- hard as a rock when dry), but the frost line isn't nearly that deep. Maybe 24" at most. Do you think the earthbags could be used here, not underground, but earth-bermed? (I wouldn't go underground on our lot as it would be too difficult to prevent water seepage in the winter.)

Kathleen

Mike Oehler

author

Posts: 60

Location: Bonners Ferry Idaho

1

posted 7 years ago

Couldn't say, Kathleen. I'd call the county extention agent and find out who in the county manages soil. Use to be called Soil Conservation Service. They are soil engineers. They might be able to advise you. I have designs for U houses for the Oregon Coast. See DVD 2 in my Underground Housing Workshop and Survival Shelter Seminar.

I'm new to the earth bag concept, seen it in a couple of books, basically just filling and stacking 'sand bags'? Is it still using a concrete foundation? Coming up with the thousands of $ for the concrete is a problem.

I wonder too about the way things sink when the ground gets wet. Long story short I was mowing about 3 months after dolly and ran out of fuel. Walked the 2 blocks to the house and back to get more and when I returned my tractor (smallish 24 hp) had sunk about a foot into the apparently solid ground. We also have a conex on the property that is on blocks that are also now under ground, that took less than a year. Thus I am concerned about seepage, and settling, even in areas that are compacted.

No frost line since it isn't supposed to freeze here, (although has) No building codes I'm in the county and it is the least densely populated county in Tx. It is the easiest place to build whatever you want there could be.

I'd believe it about at least one kind of the termites being something new to here, I did call the commercial termite folks who said the existing structure was a lost cause and doubted even tenting it would work, and the cost was insane of course.

What would keep the termites from going into the earth bags? I'm also wondering about the material the bags are made out of, both for durability and environmental issues, off gassing or degrading.

Sadly the most common method for cooling in tropical areas is air flow under the building which is impossible with a slab, I have thought of using pipe in a rock bed under it but suspect that might create more problems than it would solve, and was going to rely more on insulation, in the walls and ceiling.

Oh and I don't know about the rest of the country but rock has become insanely expensive here, about on par with redimix concrete.

Posts: 31

posted 7 years ago

Note on hill tops When I lived in Albuquerque the weather forecast always included 3 different elevations because the valley floor and the hills were surprisingly different in Temp, with the valley being the Coldest, because the wind would be funneled into the valley. Living in Eugene Or it was just the opposite, it would snow in the hills and just a few blocks away and feet lower there was none. So it is mainly a function of the location. Research research research!

Glenn Kangiser

pollinator

Posts: 236

Location: Central California

1

posted 7 years ago

Mike Oehler wrote: Glen K. -- I hope to be in CA in a couple of weeks and, if welcome, will do everything possible to visit and see your place.-- Mike O

Mike, I will do everything I can to get you here. It would be an honor. If you need accommodations we will put you up and feed you.

I will give you my contact info via e-mail. Use my e-mail button under my screen name to send me e-mail, and I will reply back to yours with the info.

It seems to me that what would attract termites would be an abundance of wood or cellulose such as in straw bales, etc - I don't think earth bags, on their own, would be very appetizing to them. I would make sure to use pressure treated wood in the structural parts that would come in contact with the earth and paint ALL wood used with boiled linseed oil - I think that would slow them down though those Korean termites sound like quite the pain in the ass.

www.asustainablelife.info

Posts: 31

posted 7 years ago

thanks Morgan, will read up, I think I would still want to cob plaster the structure for looks.

Pressure treated dosen't seem to slow them down significantly, boiled linseed is an idea though, these days I worry about my furniture since they have started coming through the floor, Maybe I'll oil around the legs at least. I'm amazed at the places they have gotten to.

Posts: 12

posted 7 years ago

You could do a test and paint a piece of PT wood with the linseed oil and put it where you know the termites will find it and see what happens. I've heard that termites can't handle borax (http://www.ehow.com/about_5127467_borax-termite-treatment.html) so you could ad some to your wall plaster (we did) to keep 'em away and then paint or plaster it with lime (which is extremely alkaline - don't know if they'd like it). Again, I'd try a test batch to see what works before you commit to anything. I feel for you, that sounds like a friggin headache!

www.asustainablelife.info

Posts: 31

posted 7 years ago

Knowing that our soil here is quite alkaline, our well is brackish too, it seems they are quite happy with alkiline. I'm going to guess that since Borax is very strong, in the 10-11 ph range maybe it is enough to finally be too much. Thinking on it, Eugene OR has rather acid soil and I never saw termites there and it isn't super cold so maybe acidity is harder on them?? I do have soda ash on hand industrial strength (use in my art) I wonder if the super high alkaline would cause problems environmentally or otherwise if I were to mix it into a cob/plaster mix

Appreciating the feed back. I posted a separate topic about the sunken 'hobbit hut' under "dirt, bottles .."

Kathleen Sanderson

Posts: 1033

Location: Near Klamath Falls, Oregon

3

posted 7 years ago

I'm not sure about the Eugene area, but there are termites on the Oregon Coast. I remember the swarms in their flying stage when we lived there.

Kathleen

Mike Oehler

author

Posts: 60

Location: Bonners Ferry Idaho

1

posted 7 years ago

Thanks for the info, Glen. I'll do my very best to get there. -- Mike Oehler

Well, Mike did make it over here last Saturday and left this morning just before 7 AM to get an early start. I just missed seeing him as I was a bit late getting up but he left a nice note. Mike is an all around great guy and welcome here any time.

Here is a link to the current conversation on the cabin and his visit. I hope to add more every so often but am currently working very steady and short on time to post.

This has been a highlight of my Underground Cabin experience. Mike mentioned years ago that he wanted to drop in when we were talking on the phone. I didn't know if it would happen but now it is done and there is no question.

Mike loves to see what has been created from his designs and hard work.

There will be an episode of Major Miracles on his http://hipnet.tv/ later that was shot here. Mike loves his satire.

Thanks Mike.

- Glenn -

Posts: 34

posted 7 years ago

After buying Mike's book, I started on a small version. The size limit for building without a permit here is 120 square feet, so I made it 10 x 12.

Well, I'm surprised that anyone even knew it was there, because it's in the middle of our 52 acres of woods. But someone made an anonymous complaint to the town selectmen, who dispatched an assessor to look at it. The assessor reported back that it was 8' x 16', which totals 128 square feet, which is a violation of the town building code. (It's actually 10' x 12', as reported above. It blows my mind that the bimbo got it that wrong. I don't believe she actually measured anything at all, I think she just eyeballed it and made up some numbers.)

She also reported that it was "within 50 feet of a pond", which is a violation of the state Shoreline Protection Act. (It's actually 52' from the shore.) So the town filed a complaint with the state Department of Environmental Services, which sent me a nasty stop-work order threatening fines and legal action. The DES tells me it will be several weeks before a "compliance enforcement inspector" can visit the site. With a title like that, I'm apprehensive that he's going to be a Nazi.

My wife and I met with the town selectmen, told them that all their measurements were off by several feet, and asked them to revisit the site and actually bring a tape measure this time. They declined to do so, but decided to drop their enforcement action. How nice of them. The bureaucratic wheels at the state DES have been set in motion, though, and we're still waiting to see what they do.

I'm relating this story to illustrate that the biggest hassles with this sort of a project might come from a completely unexpected direction, and they might not be related to construction at all.

Glenn Kangiser

pollinator

Posts: 236

Location: Central California

1

posted 7 years ago

That makes me mad...stinkin' busy bodies.

It is my understanding that you never ever have to let an assessor onto your property for any reason and they cannot even get a court order to get onto it without your permission. I understand that a building inspector can get a court order if something you are doing is hazardous to someone off of your property.

I have the following sign posted in lots of locations on my property. If someone violates it you can take them to small claims court and collect from them personally - get their name and invoice them. This includes government employees on a personal level since they decided to act illegally and elected to enter your property even though they knew there was a land use fee. The word "Land" is the key and I find that even Sheriff's do not want to admit that they read the sign, so to me that is an indication that it truly does have power.

No guarantees as so many things are done illegally by "authorities" under color of law, but if you don't know your rights it is impossible to defend yourself. If you do it may or may not be a little easier. I find it is beneficial to make them think I am crazy...

Here is the link to the start of my story and various references to my craziness throughout...

Sorry the jerks are giving you such a bad time. What area are you in - general area is fine? Just interested.

- Glenn -

Posts: 0

posted 7 years ago

The main thing I think to be concerned about that 50 foot distance is how they figure the high water mark when measuring the 50 foot required distance. There may or may not be such a consideration the the way the rules are written. In my area that makes quite a difference in some places, even though the high water mark may be seldom reached. See if you can determine that before the inspector shows up. It always helps to know is in the rule book 'they' are using.

Shipping containers can be buried if you cover with visqueen on a really dry day, build a retaining wall around them with large pavers or gabion baskets before backfilling. Backfill sides flush with top, pour 2" concrete pad over top, place rebar, pour another 2" concrete. Next lay down insulation. Cover a couple of feet, put another visqueen/poly tarp/pond liner over the top in an inverted 'V" shape like a roof, cover with another 1-4 ft of wet dirt. cost to bury a used $1800 container about $15,000. Will probably rot/rust out in 10-50 years.

SO much easier, faster and cheaper to bury a monolithic dome ecoshell! Will last for centuries, can be buried under 20 feet or rock.

Glenn Kangiser

pollinator

Posts: 236

Location: Central California

1

posted 7 years ago

Note that some have had shipping containers fail that were buried. They are made for hauling loads on ships and not engineered for side earth pressure. Seems the extra engineering and work to reinforce with concrete would be more than Mike's safe engineered design. As you mentioned, rust, moisture and condensation will be problems.

- Glenn -

Posts: 34

posted 7 years ago

don miller; MountainDon wrote: The main thing I think to be concerned about that 50 foot distance is how they figure the high water mark when measuring the 50 foot required distance. There may or may not be such a consideration the the way the rules are written. In my area that makes quite a difference in some places, even though the high water mark may be seldom reached. See if you can determine that before the inspector shows up. It always helps to know is in the rule book 'they' are using.

Good point. The state has assigned a high water elevation to the pond, 581'. I have no way of measuring that, though. Guess I just have to wait and see.

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